基于STFT和FrFT的连续波雷达参数估计

Parameter Estimation for CW Radar Based on STFT and FrFT

连续波雷达的回波信号由目标进行调制,对回波参数的估计是雷达信号处理的主要任务。本文从短时傅里叶变换(STFT)和分数阶傅里叶变换(FrFT)的基本特点入手,介绍了他们进行雷达回波信号参数估计时的优缺点。针对这些特点,提出了一种基于两种方法的混合算法。混合算法分两步:首先,混合算法运用STFT进行速度粗测;然后,用FrFT对加速度进行估计同时进行速度的精测。最后本文进行蒙特卡罗仿真实验,实验结果证明,即使在较低信噪比下该算法依然有效。

The targets can modulate the signal in continues wave（CW） radar, and the parameter estimation is the main task for radar signal processing. This paper firstly analyzes the characteristics and shortcomings of the short time Fourier transform（STFT） and the fractional Fourier transform（FrFT） in parameter estimation of the echo signal. And then a new hybrid algorithm is introduced based on these characters. The hybrid algorithm is divided into two steps： firstly, STFT is used to obtain the rough speed of the target, and then FrFT is used to estimate the acceleration and to test the precise speed. Finally, the result of the Monte-Carlo simulation experiment shows the effectiveness of the algorithm at low signal noise ratio.